Bananas and other fresh produce are typically transported from growing fields to a processing facility where they are placed in specially designed ripening rooms within a building. These ripening rooms are provided with insulated, gas-tight wall and roof panels and include an air handling unit to control the circulation and temperature of the air within the ripening room. In this manner, the ripening of the fresh produce is controlled in accordance with a predetermined ripening schedule so that the fruit is properly ripened at the time it is scheduled for delivery to retail outlets. Ethylene gas may be dispersed into the ripening room at preselected times to enable further control of the ripening of the produce. The use of ripening rooms thereby facilitates the later delivery of produce to retail outlets without the constraint of having to schedule delivery in accordance with the natural ripening process of the fruit. Use of ripening rooms also further obviates problems associated with accelerations and decelerations of the ripening process due to changing conditions during the transportation of the produce.
U.S. Pat. Nos. 4,824,685 and 5,373,780 disclose ripening rooms in which the produce is packed into unitized shipping modules including individual protective boxes that are block-stacked on pallets. The palletized produce is placed into ripening rooms having a floor, ceiling and front, rear and side walls of suitable dimensions to enclose two spaced rows of the palletized produce. The two rows are spaced apart from one another to define an interstitial volume between the rows. Sufficient spacing is also provided between the palletized produce and the ceiling and walls of the chamber to define an airspace around and above the produce.
In the patents described above, a tarp is placed over the top and one end of the spacing between the two rows of palletized produce to generally seal off the interstitial volume from the airspace around and above the produce. Exhaust fans are arranged in a sealed relation at the opposite end of the spacing between the rows to withdraw air from the interstitial volume and thereby create a pressure differential between the tarp-sealed interstitial volume and the airspace above and around the produce. Air is introduced into the airspace by an air handling unit. The air is forced by the pressure differential between the airspace and the low pressure interstitial volume to flow through openings in the sides of the boxes, circulate around the produce contained therein, and flow into the low pressure interstitial volume to be exhausted by the fans. In this manner, a forced air circulation flows throughout the produce load in the chamber. The temperature and flow rate of the air introduced into the chamber by the air handling unit can be varied to control the ripening rate of the produce.